Motivators and barriers to blood donation among potential donors of African and Caucasian ethnicity.

BACKGROUND: Minority blood donation, especially from individuals of African ethnicity, is a focus for many countries with diverse populations. As the need for antigen-negative RBC transfusions for patients with Sickle Cell Disease (SCD) continues to grow, inclusion of more African blood donors is essential to ensure this demand is met. MATERIALS AND METHODS: This study aims to explore barriers and motivators to blood donation and awareness of SCD among potential donors of diverse ethnic backgrounds in Ireland. Following ethical approval, patients attending the National Sickle Cell Disease and Thalassemia service at St James's Hospital were invited to share an online anonymous survey within their local communities to achieve snowball-sampling. RESULTS: 387 respondents completed the survey, including 311 non-donors (median age 25 years, 67% female). Ethnic backgrounds included: African or African-Irish (59%), White or Caucasian (25%), Asian (8%), Hispanic or Latino (3%), Middle Eastern (3%), Multiracial or Biracial (2%). The most commonly identified barrier overall was lack of information on blood donation. African respondents were significantly more likely to report lack of information and malaria-related barriers than Caucasians. Motivators also varied across ethnic groups, with African respondents more likely to donate to help someone within their own community or for religious motivators. Awareness of SCD was higher among African respondents. DISCUSSION: While some barriers to blood donation are shared across all ethnic groups including lack of information, notable differences exist between Caucasian and African respondents. Specific actions to recruit and retain African blood donors should focus on these key areas.

Bonsai trees in your head: how the pavlovian system sculpts goal-directed choices by pruning decision trees.

When planning a series of actions, it is usually infeasible to consider all potential future sequences; instead, one must prune the decision tree. Provably optimal pruning is, however, still computationally ruinous and the specific approximations humans employ remain unknown. We designed a new sequential reinforcement-based task and showed that human subjects adopted a simple pruning strategy: during mental evaluation of a sequence of choices, they curtailed any further evaluation of a sequence as soon as they encountered a large loss. This pruning strategy was Pavlovian: it was reflexively evoked by large losses and persisted even when overwhelmingly counterproductive. It was also evident above and beyond loss aversion. We found that the tendency towards Pavlovian pruning was selectively predicted by the degree to which subjects exhibited sub-clinical mood disturbance, in accordance with theories that ascribe Pavlovian behavioural inhibition, via serotonin, a role in mood disorders. We conclude that Pavlovian behavioural inhibition shapes highly flexible, goal-directed choices in a manner that may be important for theories of decision-making in mood disorders.